u-boot/drivers/rtc/emul_rtc.c
Simon Glass 20e442ab2d dm: Rename U_BOOT_DEVICE() to U_BOOT_DRVINFO()
The current macro is a misnomer since it does not declare a device
directly. Instead, it declares driver_info record which U-Boot uses at
runtime to create a device.

The distinction seems somewhat minor most of the time, but is becomes
quite confusing when we actually want to declare a device, with
of-platdata. We are left trying to distinguish between a device which
isn't actually device, and a device that is (perhaps an 'instance'?)

It seems better to rename this macro to describe what it actually is. The
macros is not widely used, since boards should use devicetree to declare
devices.

Rename it to U_BOOT_DRVINFO(), which indicates clearly that this is
declaring a new driver_info record, not a device.

Signed-off-by: Simon Glass <sjg@chromium.org>
2021-01-05 12:26:35 -07:00

96 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
*
* This driver emulates a real time clock based on timer ticks.
*/
#include <common.h>
#include <div64.h>
#include <dm.h>
#include <env.h>
#include <generated/timestamp_autogenerated.h>
#include <rtc.h>
/**
* struct emul_rtc - private data for emulated RTC driver
*/
struct emul_rtc {
/**
* @offset_us: microseconds from 1970-01-01 to timer_get_us() base
*/
u64 offset_us;
/**
* @isdst: daylight saving time
*/
int isdst;
};
static int emul_rtc_get(struct udevice *dev, struct rtc_time *time)
{
struct emul_rtc *priv = dev_get_priv(dev);
u64 now;
now = timer_get_us() + priv->offset_us;
do_div(now, 1000000);
rtc_to_tm(now, time);
time->tm_isdst = priv->isdst;
return 0;
}
static int emul_rtc_set(struct udevice *dev, const struct rtc_time *time)
{
struct emul_rtc *priv = dev_get_priv(dev);
if (time->tm_year < 1970)
return -EINVAL;
priv->offset_us = rtc_mktime(time) * 1000000ULL - timer_get_us();
if (time->tm_isdst > 0)
priv->isdst = 1;
else if (time->tm_isdst < 0)
priv->isdst = -1;
else
priv->isdst = 0;
return 0;
}
int emul_rtc_probe(struct udevice *dev)
{
struct emul_rtc *priv = dev_get_priv(dev);
const char *epoch_str;
u64 epoch;
epoch_str = env_get("rtc_emul_epoch");
if (epoch_str) {
epoch = simple_strtoull(epoch_str, NULL, 10);
} else {
/* Use the build date as initial time */
epoch = U_BOOT_EPOCH;
}
priv->offset_us = epoch * 1000000ULL - timer_get_us();
priv->isdst = -1;
return 0;
}
static const struct rtc_ops emul_rtc_ops = {
.get = emul_rtc_get,
.set = emul_rtc_set,
};
U_BOOT_DRIVER(rtc_emul) = {
.name = "rtc_emul",
.id = UCLASS_RTC,
.ops = &emul_rtc_ops,
.probe = emul_rtc_probe,
.priv_auto = sizeof(struct emul_rtc),
};
U_BOOT_DRVINFO(rtc_emul) = {
.name = "rtc_emul",
};